Amber was raised in Key West, Florida, and has been acting since she was very young, performing at her parents' theater, The Red Barn. She's a graduate of Boston University, where she received her BFA in acting. She also studied at the London Academy of Music and Dramatic Arts.

McDonald performed on the New York stage in such shows as Love in the Age of Narcissism and No. 11 Blue and White.

Amber's previous television credits include As The Word Turns, Guiding Light, and a 2005 episode of Law & Order: Special Victims Unit. Film credits include Searching For Bobby D., You Tell Me, Lay Me Down, Hide and Seek, and Perfect Match.